snapshot of https://github.com/livekit/livekit.git @ 08c5433449c106943231037d0b892895f6e92d3b (2026-09-15)

pkg/utils/math.go

@@ -0,0 +1,69 @@
+// Copyright 2023 LiveKit, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package utils
+
+import (
+	"cmp"
+	"slices"
+)
+
+// OrderedNumber defines a constraint for numeric types that can be ordered and divided.
+type OrderedNumber interface {
+	cmp.Ordered
+	~int | ~int8 | ~int16 | ~int32 | ~int64 |
+		~uint | ~uint8 | ~uint16 | ~uint32 | ~uint64 |
+		~uintptr | ~float32 | ~float64
+}
+
+// Median gets the median value for a slice without modifying the original slice.
+//
+// Note:
+// 1. For integer types, if the slice has an even length, the division (/ 2)
+//    is performed using integer division, which truncates the result towards zero.
+// 2. Uses an overflow-safe formula left + (right-left)/2 to support narrow integer types.
+func Median[T OrderedNumber](input []T) T {
+	num := len(input)
+	switch num {
+	case 0:
+		var zero T
+		return zero
+	case 1:
+		return input[0]
+	}
+
+	// Clone the slice to avoid mutating the caller's slice
+	sortedInput := slices.Clone(input)
+	slices.Sort(sortedInput)
+
+	if num%2 != 0 {
+		return sortedInput[num/2]
+	}
+	left := sortedInput[num/2-1]
+	right := sortedInput[num/2]
+	return left + (right-left)/T(2)
+}
+
+func Signum[T int | int8 | int16 | int32 | int64 | float32 | float64](val T) int {
+	switch {
+	case val < 0:
+		return -1
+
+	case val > 0:
+		return 1
+
+	default:
+		return 0
+	}
+}